 Hello everyone, I'm Dr. Rajita, junior resident in the department of radio diagnosis at KMC Manipal. My topic is imaging features of hepatocellular carcinoma post-taste of pictorial assay. The purpose of this is to show the imaging features of hepatocellular carcinoma after trans-schedeter arterial chemoembalisation on CT and describe its use in evaluating the response to therapy. Patients diagnosed with HSEC who underwent taste at our hospital were followed up to CT scan to study different imaging features and the study is the illustration of representative cases. Taste is a local regional treatment for inoperable primary or secondary hepatic malignancies. It induces tumor ischemia and provides high prolonged local chemotherapy concentration, takes advantage of fact that hepatic cancers receive blood supply primarily from hepatic artery whereas liver parankyma has dual supply from hepatic artery and portal vein making it less susceptible to injected chemo-therapeutic agents. Conventional taste it uses lipidol as the chemo-therapeutic carrier agent followed by particulate embolisation drug-illuting bead taste is the chemo-therapeutic call delivery and embolisation using beads impregnated with the chemo-therapeutic agent. Trans arterial embolisation is the particulate embolisation without chemo-therapeutic agent using PVA. First procedural imaging the goals are to look at residual or recurrent tumor requiring further treatment, identify complications of therapy, detect and characterize new or additional observations elsewhere in the liver. CT is commonly used as the standard imaging technique for evaluating therapeutic response in patients with HCC aftertaste. So the tumor response is most commonly given by modified resist criteria that is the complete response is the disappearance of any intratumoral arterial enhancement. The treatment response is the increase in 30% or decrease in 30% of the diameter of the viable target lesion. Stable disease is any case that doesn't fit into complete partial or progressive disease. Progressive disease is increase of at least 20% in the diameter of the viable target lesion. For Lyride, so it is treatment response it can either be non-viable, equivocal or viable. Viable is when there is arterial phase hyper enhancement wash out appearance or enhancement similar to that of pre-treatment. Non-viable is no-lesional enhancement on treatment specific expected enhancement pattern. We have a case of 60 year old male with multi-centric HCC who underwent TAS and on follow-up CT. It shows 63% increase in the single largest diameter of the lesion in segment 7 or 8 which is suggestive of progressive disease. Another case showing multiple well-defined peripherally enhancing around lesions which on follow-up CT show no increase in the single largest diameter which is suggestive of stable disease. Here we can see a large lesion which is showing arterially peripheral enhancing components which on follow-up CT show decrease in the arterially enhancing components with the peripheral lipidol deposition. So there are different features on imaging that can help us to know whether the tumor is viable or not. So no-lesional enhancement is the absence of enhancement within or along the margin of the lesion which makes it non-viable whereas post-treatment arterial phase hyper enhancement or post-treatment wash out or post-treatment enhancement similar to pre-treatment all are suggestive of viable tumor. The accumulation of iodized oil lipidol is observed on pre-contrast CT and it can be classified into no lipidol deposition, homogenous or patchy incomplete lipidol retention. Homogenous or patchy complete lipidol reduction if defective uptake of iodized oil that is lipidol is seen then it suggests there is remain in viable tissue. So here we can see a 64 year old male with HCC lesion in segments 5 and 6 showing complete patchy lipidol retention post-treatment. Another case where it shows incomplete patchy lipidol retention in this large lesion whereas it shows complete homogenous lipidol retention in a smaller lesion adjacent to it. Another is 66 year old male with LR5 lesion, the small lesion which shows incomplete homogenous lipidol retention. Here we can see this 67 year old male with cirrhosis of liver and HCC which shows incomplete lipidol homogenous lipidol retention pattern. So the complications that can be detected on CT or hepatic abscess, chemical, cholestitis, biliary stricter on necrosis, here we have this case of 67 year old male who underwent taste for liver lesion in segment 5, 7 and 8 who presented 2 weeks later with pain, abdomen and fever. The CT scan post-treatment showed lipidol deposition with multiple air foci and nemobilia which is suggestive of probable anaerobic infection. So the role of CT is to look at residual recurrent tumors and detect any new lesions. Here we can see the 62 year old male patient with cirrhosis who underwent taste for this lesion in a year. This is the pre-taste CT on post-taste CTs. We can see there is still arterially enhancing component. Also there is a wash out and portovino space with necrotic areas within. These are the hypodense areas within. There is also evidence of new arterially enhancing lesion in segment 7. So post-procedure imaging and clinical assessment, if the remaining untreated tumor is there, so then we have to clinically assess it 4 weeks after initial treatment. So if the candidate is good for local regional therapy, then a taste is planned for 4-8 weeks after the initial taste. If not then we have to wait until the status improves. If all areas of tumor have been treated with taste then the imaging assessment is 4 weeks after the last treatment. Viable tumor on imaging, if it is present it can be secondary to untreated, under treated hepatic branches on initial taste or secondary to aberrant or extra hepatic arterial supply. If there is no viable tumor on imaging it can be complete imaging response which has to be followed up in 3 months with imaging. So CT is the standard imaging technique for monitoring the effectiveness of taste. Interval retention pattern may play an important role in treatment efficacy. The imaging follow-up schedule varies from institution to institution but 1 month to 3 month is what is followed in some centers. The short interval follow-up studies allow quick retreatment in case where there is recurrent tumor or development of new tumor. These are my references.